Mercer Island, WA · King County
MERCER ISLAND CITY OF Water System
Consumer Confidence Report status
MERCER ISLAND CITY OF must publish a Consumer Confidence Report — the annual drinking water quality report covering calendar year 2026 — by July 1, 2027.
As of August 1, 2026, EPA's federal records show no open violations for MERCER ISLAND CITY OF.
Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed August 1, 2026. This is a record-keeping and public-information tool — it does not replace Washington’s official records. Always confirm current status with Washington before making decisions based on this information.
System facts
- System ID (PWSID)
- WA5353640
- System type
- Community Water System
- Population served
- 31,057
- Service connections
- 9,807
- Ownership
- local government
- Water source
- surface water (rivers, lakes, or reservoirs)
MERCER ISLAND CITY OF is one of 111 community water systems in Washington in the 10,001 to 100,000 people size category, serving 31,057 people from surface water.
As of August 1, 2026, its federal record holds 2 entries in 1992, all of which EPA lists as closed. Nothing has been added since 1992.
All 2 are monitoring and reporting requirements — the category that accounts for about four in five of all violations in EPA's national dataset — rather than findings about the water itself. The record involves the Total Coliform Rules.
Violation history
Monitoring, Routine Minor (TCR)
—Coliform (TCR)
December 1, 1992 – December 31, 1992
ArchivedMonitoring, Routine Minor (TCR)
—Coliform (TCR)
August 1, 1992 – August 31, 1992
Archived
Archived closed in EPA's records (typically due to age or a data correction)
| Period | Violation | Contaminant / rule | Health-based | Status |
|---|---|---|---|---|
| December 1, 1992 – December 31, 1992 | Monitoring, Routine Minor (TCR) | Coliform (TCR) | — | Archived |
| August 1, 1992 – August 31, 1992 | Monitoring, Routine Minor (TCR) | Coliform (TCR) | — | Archived |
Archived closed in EPA's records (typically due to age or a data correction)
Enforcement actions
- December 31, 1992State Violation/Reminder Notice1 linked violation
- August 31, 1992State Violation/Reminder Notice1 linked violation
- January 31, 1992State Violation/Reminder Notice1 linked violation
Common questions
Is MERCER ISLAND CITY OF required to publish a Consumer Confidence Report?
- Yes. MERCER ISLAND CITY OF is a community water system, and federal rules (40 CFR 141 Subpart O) require every community water system to publish a Consumer Confidence Report each year.
When is MERCER ISLAND CITY OF’s next Consumer Confidence Report due?
- MERCER ISLAND CITY OF’s next Consumer Confidence Report is due by July 1, 2027. The report covers calendar year 2026.
Does MERCER ISLAND CITY OF have any open drinking water violations on record?
- As of August 1, 2026, EPA's federal records show no open violations for MERCER ISLAND CITY OF.
What is a Consumer Confidence Report?
- A Consumer Confidence Report (CCR) is the annual drinking water quality report that community water systems must provide to the people they serve. It lists the contaminants detected in the system’s water during the year, where the water comes from, and how the results compare with federal limits. EPA’s revised CCR rule takes effect January 1, 2027, and the first reports in the new format are due July 1, 2027.
Contact
MERCER ISLAND CITY OF
Phone not on record
Mercer Island, WA 98040